1 //===--- CGExprComplex.cpp - Emit LLVM Code for Complex Exprs -------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This contains code to emit Expr nodes with complex types as LLVM code.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "CodeGenFunction.h"
15 #include "CodeGenModule.h"
16 #include "clang/AST/ASTContext.h"
17 #include "clang/AST/StmtVisitor.h"
18 #include "llvm/Constants.h"
19 #include "llvm/Function.h"
20 #include "llvm/ADT/SmallString.h"
21 using namespace clang;
22 using namespace CodeGen;
23 
24 //===----------------------------------------------------------------------===//
25 //                        Complex Expression Emitter
26 //===----------------------------------------------------------------------===//
27 
28 typedef CodeGenFunction::ComplexPairTy ComplexPairTy;
29 
30 namespace  {
31 class ComplexExprEmitter
32   : public StmtVisitor<ComplexExprEmitter, ComplexPairTy> {
33   CodeGenFunction &CGF;
34   CGBuilderTy &Builder;
35   // True is we should ignore the value of a
36   bool IgnoreReal;
37   bool IgnoreImag;
38 public:
39   ComplexExprEmitter(CodeGenFunction &cgf, bool ir=false, bool ii=false)
40     : CGF(cgf), Builder(CGF.Builder), IgnoreReal(ir), IgnoreImag(ii) {
41   }
42 
43 
44   //===--------------------------------------------------------------------===//
45   //                               Utilities
46   //===--------------------------------------------------------------------===//
47 
48   bool TestAndClearIgnoreReal() {
49     bool I = IgnoreReal;
50     IgnoreReal = false;
51     return I;
52   }
53   bool TestAndClearIgnoreImag() {
54     bool I = IgnoreImag;
55     IgnoreImag = false;
56     return I;
57   }
58 
59   /// EmitLoadOfLValue - Given an expression with complex type that represents a
60   /// value l-value, this method emits the address of the l-value, then loads
61   /// and returns the result.
62   ComplexPairTy EmitLoadOfLValue(const Expr *E) {
63     return EmitLoadOfLValue(CGF.EmitLValue(E));
64   }
65 
66   ComplexPairTy EmitLoadOfLValue(LValue LV) {
67     assert(LV.isSimple() && "complex l-value must be simple");
68     return EmitLoadOfComplex(LV.getAddress(), LV.isVolatileQualified());
69   }
70 
71   /// EmitLoadOfComplex - Given a pointer to a complex value, emit code to load
72   /// the real and imaginary pieces.
73   ComplexPairTy EmitLoadOfComplex(llvm::Value *SrcPtr, bool isVolatile);
74 
75   /// EmitStoreThroughLValue - Given an l-value of complex type, store
76   /// a complex number into it.
77   void EmitStoreThroughLValue(ComplexPairTy Val, LValue LV) {
78     assert(LV.isSimple() && "complex l-value must be simple");
79     return EmitStoreOfComplex(Val, LV.getAddress(), LV.isVolatileQualified());
80   }
81 
82   /// EmitStoreOfComplex - Store the specified real/imag parts into the
83   /// specified value pointer.
84   void EmitStoreOfComplex(ComplexPairTy Val, llvm::Value *ResPtr, bool isVol);
85 
86   /// EmitComplexToComplexCast - Emit a cast from complex value Val to DestType.
87   ComplexPairTy EmitComplexToComplexCast(ComplexPairTy Val, QualType SrcType,
88                                          QualType DestType);
89 
90   //===--------------------------------------------------------------------===//
91   //                            Visitor Methods
92   //===--------------------------------------------------------------------===//
93 
94   ComplexPairTy Visit(Expr *E) {
95     return StmtVisitor<ComplexExprEmitter, ComplexPairTy>::Visit(E);
96   }
97 
98   ComplexPairTy VisitStmt(Stmt *S) {
99     S->dump(CGF.getContext().getSourceManager());
100     llvm_unreachable("Stmt can't have complex result type!");
101   }
102   ComplexPairTy VisitExpr(Expr *S);
103   ComplexPairTy VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr());}
104   ComplexPairTy VisitGenericSelectionExpr(GenericSelectionExpr *GE) {
105     return Visit(GE->getResultExpr());
106   }
107   ComplexPairTy VisitImaginaryLiteral(const ImaginaryLiteral *IL);
108   ComplexPairTy
109   VisitSubstNonTypeTemplateParmExpr(SubstNonTypeTemplateParmExpr *PE) {
110     return Visit(PE->getReplacement());
111   }
112 
113   // l-values.
114   ComplexPairTy VisitDeclRefExpr(const Expr *E) { return EmitLoadOfLValue(E); }
115   ComplexPairTy VisitBlockDeclRefExpr(const Expr *E) { return EmitLoadOfLValue(E); }
116   ComplexPairTy VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) {
117     return EmitLoadOfLValue(E);
118   }
119   ComplexPairTy VisitObjCMessageExpr(ObjCMessageExpr *E) {
120     return CGF.EmitObjCMessageExpr(E).getComplexVal();
121   }
122   ComplexPairTy VisitArraySubscriptExpr(Expr *E) { return EmitLoadOfLValue(E); }
123   ComplexPairTy VisitMemberExpr(const Expr *E) { return EmitLoadOfLValue(E); }
124   ComplexPairTy VisitOpaqueValueExpr(OpaqueValueExpr *E) {
125     if (E->isGLValue())
126       return EmitLoadOfLValue(CGF.getOpaqueLValueMapping(E));
127     return CGF.getOpaqueRValueMapping(E).getComplexVal();
128   }
129 
130   ComplexPairTy VisitPseudoObjectExpr(PseudoObjectExpr *E) {
131     return CGF.EmitPseudoObjectRValue(E).getComplexVal();
132   }
133 
134   // FIXME: CompoundLiteralExpr
135 
136   ComplexPairTy EmitCast(CastExpr::CastKind CK, Expr *Op, QualType DestTy);
137   ComplexPairTy VisitImplicitCastExpr(ImplicitCastExpr *E) {
138     // Unlike for scalars, we don't have to worry about function->ptr demotion
139     // here.
140     return EmitCast(E->getCastKind(), E->getSubExpr(), E->getType());
141   }
142   ComplexPairTy VisitCastExpr(CastExpr *E) {
143     return EmitCast(E->getCastKind(), E->getSubExpr(), E->getType());
144   }
145   ComplexPairTy VisitCallExpr(const CallExpr *E);
146   ComplexPairTy VisitStmtExpr(const StmtExpr *E);
147 
148   // Operators.
149   ComplexPairTy VisitPrePostIncDec(const UnaryOperator *E,
150                                    bool isInc, bool isPre) {
151     LValue LV = CGF.EmitLValue(E->getSubExpr());
152     return CGF.EmitComplexPrePostIncDec(E, LV, isInc, isPre);
153   }
154   ComplexPairTy VisitUnaryPostDec(const UnaryOperator *E) {
155     return VisitPrePostIncDec(E, false, false);
156   }
157   ComplexPairTy VisitUnaryPostInc(const UnaryOperator *E) {
158     return VisitPrePostIncDec(E, true, false);
159   }
160   ComplexPairTy VisitUnaryPreDec(const UnaryOperator *E) {
161     return VisitPrePostIncDec(E, false, true);
162   }
163   ComplexPairTy VisitUnaryPreInc(const UnaryOperator *E) {
164     return VisitPrePostIncDec(E, true, true);
165   }
166   ComplexPairTy VisitUnaryDeref(const Expr *E) { return EmitLoadOfLValue(E); }
167   ComplexPairTy VisitUnaryPlus     (const UnaryOperator *E) {
168     TestAndClearIgnoreReal();
169     TestAndClearIgnoreImag();
170     return Visit(E->getSubExpr());
171   }
172   ComplexPairTy VisitUnaryMinus    (const UnaryOperator *E);
173   ComplexPairTy VisitUnaryNot      (const UnaryOperator *E);
174   // LNot,Real,Imag never return complex.
175   ComplexPairTy VisitUnaryExtension(const UnaryOperator *E) {
176     return Visit(E->getSubExpr());
177   }
178   ComplexPairTy VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) {
179     return Visit(DAE->getExpr());
180   }
181   ComplexPairTy VisitExprWithCleanups(ExprWithCleanups *E) {
182     CGF.enterFullExpression(E);
183     CodeGenFunction::RunCleanupsScope Scope(CGF);
184     return Visit(E->getSubExpr());
185   }
186   ComplexPairTy VisitCXXScalarValueInitExpr(CXXScalarValueInitExpr *E) {
187     assert(E->getType()->isAnyComplexType() && "Expected complex type!");
188     QualType Elem = E->getType()->getAs<ComplexType>()->getElementType();
189     llvm::Constant *Null = llvm::Constant::getNullValue(CGF.ConvertType(Elem));
190     return ComplexPairTy(Null, Null);
191   }
192   ComplexPairTy VisitImplicitValueInitExpr(ImplicitValueInitExpr *E) {
193     assert(E->getType()->isAnyComplexType() && "Expected complex type!");
194     QualType Elem = E->getType()->getAs<ComplexType>()->getElementType();
195     llvm::Constant *Null =
196                        llvm::Constant::getNullValue(CGF.ConvertType(Elem));
197     return ComplexPairTy(Null, Null);
198   }
199 
200   struct BinOpInfo {
201     ComplexPairTy LHS;
202     ComplexPairTy RHS;
203     QualType Ty;  // Computation Type.
204   };
205 
206   BinOpInfo EmitBinOps(const BinaryOperator *E);
207   LValue EmitCompoundAssignLValue(const CompoundAssignOperator *E,
208                                   ComplexPairTy (ComplexExprEmitter::*Func)
209                                   (const BinOpInfo &),
210                                   ComplexPairTy &Val);
211   ComplexPairTy EmitCompoundAssign(const CompoundAssignOperator *E,
212                                    ComplexPairTy (ComplexExprEmitter::*Func)
213                                    (const BinOpInfo &));
214 
215   ComplexPairTy EmitBinAdd(const BinOpInfo &Op);
216   ComplexPairTy EmitBinSub(const BinOpInfo &Op);
217   ComplexPairTy EmitBinMul(const BinOpInfo &Op);
218   ComplexPairTy EmitBinDiv(const BinOpInfo &Op);
219 
220   ComplexPairTy VisitBinAdd(const BinaryOperator *E) {
221     return EmitBinAdd(EmitBinOps(E));
222   }
223   ComplexPairTy VisitBinSub(const BinaryOperator *E) {
224     return EmitBinSub(EmitBinOps(E));
225   }
226   ComplexPairTy VisitBinMul(const BinaryOperator *E) {
227     return EmitBinMul(EmitBinOps(E));
228   }
229   ComplexPairTy VisitBinDiv(const BinaryOperator *E) {
230     return EmitBinDiv(EmitBinOps(E));
231   }
232 
233   // Compound assignments.
234   ComplexPairTy VisitBinAddAssign(const CompoundAssignOperator *E) {
235     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinAdd);
236   }
237   ComplexPairTy VisitBinSubAssign(const CompoundAssignOperator *E) {
238     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinSub);
239   }
240   ComplexPairTy VisitBinMulAssign(const CompoundAssignOperator *E) {
241     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinMul);
242   }
243   ComplexPairTy VisitBinDivAssign(const CompoundAssignOperator *E) {
244     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinDiv);
245   }
246 
247   // GCC rejects rem/and/or/xor for integer complex.
248   // Logical and/or always return int, never complex.
249 
250   // No comparisons produce a complex result.
251 
252   LValue EmitBinAssignLValue(const BinaryOperator *E,
253                              ComplexPairTy &Val);
254   ComplexPairTy VisitBinAssign     (const BinaryOperator *E);
255   ComplexPairTy VisitBinComma      (const BinaryOperator *E);
256 
257 
258   ComplexPairTy
259   VisitAbstractConditionalOperator(const AbstractConditionalOperator *CO);
260   ComplexPairTy VisitChooseExpr(ChooseExpr *CE);
261 
262   ComplexPairTy VisitInitListExpr(InitListExpr *E);
263 
264   ComplexPairTy VisitVAArgExpr(VAArgExpr *E);
265 
266   ComplexPairTy VisitAtomicExpr(AtomicExpr *E) {
267     return CGF.EmitAtomicExpr(E).getComplexVal();
268   }
269 };
270 }  // end anonymous namespace.
271 
272 //===----------------------------------------------------------------------===//
273 //                                Utilities
274 //===----------------------------------------------------------------------===//
275 
276 /// EmitLoadOfComplex - Given an RValue reference for a complex, emit code to
277 /// load the real and imaginary pieces, returning them as Real/Imag.
278 ComplexPairTy ComplexExprEmitter::EmitLoadOfComplex(llvm::Value *SrcPtr,
279                                                     bool isVolatile) {
280   llvm::Value *Real=0, *Imag=0;
281 
282   if (!IgnoreReal || isVolatile) {
283     llvm::Value *RealP = Builder.CreateStructGEP(SrcPtr, 0,
284                                                  SrcPtr->getName() + ".realp");
285     Real = Builder.CreateLoad(RealP, isVolatile, SrcPtr->getName() + ".real");
286   }
287 
288   if (!IgnoreImag || isVolatile) {
289     llvm::Value *ImagP = Builder.CreateStructGEP(SrcPtr, 1,
290                                                  SrcPtr->getName() + ".imagp");
291     Imag = Builder.CreateLoad(ImagP, isVolatile, SrcPtr->getName() + ".imag");
292   }
293   return ComplexPairTy(Real, Imag);
294 }
295 
296 /// EmitStoreOfComplex - Store the specified real/imag parts into the
297 /// specified value pointer.
298 void ComplexExprEmitter::EmitStoreOfComplex(ComplexPairTy Val, llvm::Value *Ptr,
299                                             bool isVolatile) {
300   llvm::Value *RealPtr = Builder.CreateStructGEP(Ptr, 0, "real");
301   llvm::Value *ImagPtr = Builder.CreateStructGEP(Ptr, 1, "imag");
302 
303   Builder.CreateStore(Val.first, RealPtr, isVolatile);
304   Builder.CreateStore(Val.second, ImagPtr, isVolatile);
305 }
306 
307 
308 
309 //===----------------------------------------------------------------------===//
310 //                            Visitor Methods
311 //===----------------------------------------------------------------------===//
312 
313 ComplexPairTy ComplexExprEmitter::VisitExpr(Expr *E) {
314   CGF.ErrorUnsupported(E, "complex expression");
315   llvm::Type *EltTy =
316   CGF.ConvertType(E->getType()->getAs<ComplexType>()->getElementType());
317   llvm::Value *U = llvm::UndefValue::get(EltTy);
318   return ComplexPairTy(U, U);
319 }
320 
321 ComplexPairTy ComplexExprEmitter::
322 VisitImaginaryLiteral(const ImaginaryLiteral *IL) {
323   llvm::Value *Imag = CGF.EmitScalarExpr(IL->getSubExpr());
324   return ComplexPairTy(llvm::Constant::getNullValue(Imag->getType()), Imag);
325 }
326 
327 
328 ComplexPairTy ComplexExprEmitter::VisitCallExpr(const CallExpr *E) {
329   if (E->getCallReturnType()->isReferenceType())
330     return EmitLoadOfLValue(E);
331 
332   return CGF.EmitCallExpr(E).getComplexVal();
333 }
334 
335 ComplexPairTy ComplexExprEmitter::VisitStmtExpr(const StmtExpr *E) {
336   CodeGenFunction::StmtExprEvaluation eval(CGF);
337   return CGF.EmitCompoundStmt(*E->getSubStmt(), true).getComplexVal();
338 }
339 
340 /// EmitComplexToComplexCast - Emit a cast from complex value Val to DestType.
341 ComplexPairTy ComplexExprEmitter::EmitComplexToComplexCast(ComplexPairTy Val,
342                                                            QualType SrcType,
343                                                            QualType DestType) {
344   // Get the src/dest element type.
345   SrcType = SrcType->getAs<ComplexType>()->getElementType();
346   DestType = DestType->getAs<ComplexType>()->getElementType();
347 
348   // C99 6.3.1.6: When a value of complex type is converted to another
349   // complex type, both the real and imaginary parts follow the conversion
350   // rules for the corresponding real types.
351   Val.first = CGF.EmitScalarConversion(Val.first, SrcType, DestType);
352   Val.second = CGF.EmitScalarConversion(Val.second, SrcType, DestType);
353   return Val;
354 }
355 
356 ComplexPairTy ComplexExprEmitter::EmitCast(CastExpr::CastKind CK, Expr *Op,
357                                            QualType DestTy) {
358   switch (CK) {
359   case CK_Dependent: llvm_unreachable("dependent cast kind in IR gen!");
360 
361   case CK_NoOp:
362   case CK_LValueToRValue:
363   case CK_UserDefinedConversion:
364     return Visit(Op);
365 
366   case CK_LValueBitCast: {
367     llvm::Value *V = CGF.EmitLValue(Op).getAddress();
368     V = Builder.CreateBitCast(V,
369                     CGF.ConvertType(CGF.getContext().getPointerType(DestTy)));
370     // FIXME: Are the qualifiers correct here?
371     return EmitLoadOfComplex(V, DestTy.isVolatileQualified());
372   }
373 
374   case CK_BitCast:
375   case CK_BaseToDerived:
376   case CK_DerivedToBase:
377   case CK_UncheckedDerivedToBase:
378   case CK_Dynamic:
379   case CK_ToUnion:
380   case CK_ArrayToPointerDecay:
381   case CK_FunctionToPointerDecay:
382   case CK_NullToPointer:
383   case CK_NullToMemberPointer:
384   case CK_BaseToDerivedMemberPointer:
385   case CK_DerivedToBaseMemberPointer:
386   case CK_MemberPointerToBoolean:
387   case CK_ConstructorConversion:
388   case CK_IntegralToPointer:
389   case CK_PointerToIntegral:
390   case CK_PointerToBoolean:
391   case CK_ToVoid:
392   case CK_VectorSplat:
393   case CK_IntegralCast:
394   case CK_IntegralToBoolean:
395   case CK_IntegralToFloating:
396   case CK_FloatingToIntegral:
397   case CK_FloatingToBoolean:
398   case CK_FloatingCast:
399   case CK_CPointerToObjCPointerCast:
400   case CK_BlockPointerToObjCPointerCast:
401   case CK_AnyPointerToBlockPointerCast:
402   case CK_ObjCObjectLValueCast:
403   case CK_FloatingComplexToReal:
404   case CK_FloatingComplexToBoolean:
405   case CK_IntegralComplexToReal:
406   case CK_IntegralComplexToBoolean:
407   case CK_ARCProduceObject:
408   case CK_ARCConsumeObject:
409   case CK_ARCReclaimReturnedObject:
410   case CK_ARCExtendBlockObject:
411     llvm_unreachable("invalid cast kind for complex value");
412 
413   case CK_FloatingRealToComplex:
414   case CK_IntegralRealToComplex: {
415     llvm::Value *Elt = CGF.EmitScalarExpr(Op);
416 
417     // Convert the input element to the element type of the complex.
418     DestTy = DestTy->getAs<ComplexType>()->getElementType();
419     Elt = CGF.EmitScalarConversion(Elt, Op->getType(), DestTy);
420 
421     // Return (realval, 0).
422     return ComplexPairTy(Elt, llvm::Constant::getNullValue(Elt->getType()));
423   }
424 
425   case CK_FloatingComplexCast:
426   case CK_FloatingComplexToIntegralComplex:
427   case CK_IntegralComplexCast:
428   case CK_IntegralComplexToFloatingComplex:
429     return EmitComplexToComplexCast(Visit(Op), Op->getType(), DestTy);
430   }
431 
432   llvm_unreachable("unknown cast resulting in complex value");
433 }
434 
435 ComplexPairTy ComplexExprEmitter::VisitUnaryMinus(const UnaryOperator *E) {
436   TestAndClearIgnoreReal();
437   TestAndClearIgnoreImag();
438   ComplexPairTy Op = Visit(E->getSubExpr());
439 
440   llvm::Value *ResR, *ResI;
441   if (Op.first->getType()->isFloatingPointTy()) {
442     ResR = Builder.CreateFNeg(Op.first,  "neg.r");
443     ResI = Builder.CreateFNeg(Op.second, "neg.i");
444   } else {
445     ResR = Builder.CreateNeg(Op.first,  "neg.r");
446     ResI = Builder.CreateNeg(Op.second, "neg.i");
447   }
448   return ComplexPairTy(ResR, ResI);
449 }
450 
451 ComplexPairTy ComplexExprEmitter::VisitUnaryNot(const UnaryOperator *E) {
452   TestAndClearIgnoreReal();
453   TestAndClearIgnoreImag();
454   // ~(a+ib) = a + i*-b
455   ComplexPairTy Op = Visit(E->getSubExpr());
456   llvm::Value *ResI;
457   if (Op.second->getType()->isFloatingPointTy())
458     ResI = Builder.CreateFNeg(Op.second, "conj.i");
459   else
460     ResI = Builder.CreateNeg(Op.second, "conj.i");
461 
462   return ComplexPairTy(Op.first, ResI);
463 }
464 
465 ComplexPairTy ComplexExprEmitter::EmitBinAdd(const BinOpInfo &Op) {
466   llvm::Value *ResR, *ResI;
467 
468   if (Op.LHS.first->getType()->isFloatingPointTy()) {
469     ResR = Builder.CreateFAdd(Op.LHS.first,  Op.RHS.first,  "add.r");
470     ResI = Builder.CreateFAdd(Op.LHS.second, Op.RHS.second, "add.i");
471   } else {
472     ResR = Builder.CreateAdd(Op.LHS.first,  Op.RHS.first,  "add.r");
473     ResI = Builder.CreateAdd(Op.LHS.second, Op.RHS.second, "add.i");
474   }
475   return ComplexPairTy(ResR, ResI);
476 }
477 
478 ComplexPairTy ComplexExprEmitter::EmitBinSub(const BinOpInfo &Op) {
479   llvm::Value *ResR, *ResI;
480   if (Op.LHS.first->getType()->isFloatingPointTy()) {
481     ResR = Builder.CreateFSub(Op.LHS.first,  Op.RHS.first,  "sub.r");
482     ResI = Builder.CreateFSub(Op.LHS.second, Op.RHS.second, "sub.i");
483   } else {
484     ResR = Builder.CreateSub(Op.LHS.first,  Op.RHS.first,  "sub.r");
485     ResI = Builder.CreateSub(Op.LHS.second, Op.RHS.second, "sub.i");
486   }
487   return ComplexPairTy(ResR, ResI);
488 }
489 
490 
491 ComplexPairTy ComplexExprEmitter::EmitBinMul(const BinOpInfo &Op) {
492   using llvm::Value;
493   Value *ResR, *ResI;
494 
495   if (Op.LHS.first->getType()->isFloatingPointTy()) {
496     Value *ResRl = Builder.CreateFMul(Op.LHS.first, Op.RHS.first, "mul.rl");
497     Value *ResRr = Builder.CreateFMul(Op.LHS.second, Op.RHS.second,"mul.rr");
498     ResR  = Builder.CreateFSub(ResRl, ResRr, "mul.r");
499 
500     Value *ResIl = Builder.CreateFMul(Op.LHS.second, Op.RHS.first, "mul.il");
501     Value *ResIr = Builder.CreateFMul(Op.LHS.first, Op.RHS.second, "mul.ir");
502     ResI  = Builder.CreateFAdd(ResIl, ResIr, "mul.i");
503   } else {
504     Value *ResRl = Builder.CreateMul(Op.LHS.first, Op.RHS.first, "mul.rl");
505     Value *ResRr = Builder.CreateMul(Op.LHS.second, Op.RHS.second,"mul.rr");
506     ResR  = Builder.CreateSub(ResRl, ResRr, "mul.r");
507 
508     Value *ResIl = Builder.CreateMul(Op.LHS.second, Op.RHS.first, "mul.il");
509     Value *ResIr = Builder.CreateMul(Op.LHS.first, Op.RHS.second, "mul.ir");
510     ResI  = Builder.CreateAdd(ResIl, ResIr, "mul.i");
511   }
512   return ComplexPairTy(ResR, ResI);
513 }
514 
515 ComplexPairTy ComplexExprEmitter::EmitBinDiv(const BinOpInfo &Op) {
516   llvm::Value *LHSr = Op.LHS.first, *LHSi = Op.LHS.second;
517   llvm::Value *RHSr = Op.RHS.first, *RHSi = Op.RHS.second;
518 
519 
520   llvm::Value *DSTr, *DSTi;
521   if (Op.LHS.first->getType()->isFloatingPointTy()) {
522     // (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd))
523     llvm::Value *Tmp1 = Builder.CreateFMul(LHSr, RHSr); // a*c
524     llvm::Value *Tmp2 = Builder.CreateFMul(LHSi, RHSi); // b*d
525     llvm::Value *Tmp3 = Builder.CreateFAdd(Tmp1, Tmp2); // ac+bd
526 
527     llvm::Value *Tmp4 = Builder.CreateFMul(RHSr, RHSr); // c*c
528     llvm::Value *Tmp5 = Builder.CreateFMul(RHSi, RHSi); // d*d
529     llvm::Value *Tmp6 = Builder.CreateFAdd(Tmp4, Tmp5); // cc+dd
530 
531     llvm::Value *Tmp7 = Builder.CreateFMul(LHSi, RHSr); // b*c
532     llvm::Value *Tmp8 = Builder.CreateFMul(LHSr, RHSi); // a*d
533     llvm::Value *Tmp9 = Builder.CreateFSub(Tmp7, Tmp8); // bc-ad
534 
535     DSTr = Builder.CreateFDiv(Tmp3, Tmp6);
536     DSTi = Builder.CreateFDiv(Tmp9, Tmp6);
537   } else {
538     // (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd))
539     llvm::Value *Tmp1 = Builder.CreateMul(LHSr, RHSr); // a*c
540     llvm::Value *Tmp2 = Builder.CreateMul(LHSi, RHSi); // b*d
541     llvm::Value *Tmp3 = Builder.CreateAdd(Tmp1, Tmp2); // ac+bd
542 
543     llvm::Value *Tmp4 = Builder.CreateMul(RHSr, RHSr); // c*c
544     llvm::Value *Tmp5 = Builder.CreateMul(RHSi, RHSi); // d*d
545     llvm::Value *Tmp6 = Builder.CreateAdd(Tmp4, Tmp5); // cc+dd
546 
547     llvm::Value *Tmp7 = Builder.CreateMul(LHSi, RHSr); // b*c
548     llvm::Value *Tmp8 = Builder.CreateMul(LHSr, RHSi); // a*d
549     llvm::Value *Tmp9 = Builder.CreateSub(Tmp7, Tmp8); // bc-ad
550 
551     if (Op.Ty->getAs<ComplexType>()->getElementType()->isUnsignedIntegerType()) {
552       DSTr = Builder.CreateUDiv(Tmp3, Tmp6);
553       DSTi = Builder.CreateUDiv(Tmp9, Tmp6);
554     } else {
555       DSTr = Builder.CreateSDiv(Tmp3, Tmp6);
556       DSTi = Builder.CreateSDiv(Tmp9, Tmp6);
557     }
558   }
559 
560   return ComplexPairTy(DSTr, DSTi);
561 }
562 
563 ComplexExprEmitter::BinOpInfo
564 ComplexExprEmitter::EmitBinOps(const BinaryOperator *E) {
565   TestAndClearIgnoreReal();
566   TestAndClearIgnoreImag();
567   BinOpInfo Ops;
568   Ops.LHS = Visit(E->getLHS());
569   Ops.RHS = Visit(E->getRHS());
570   Ops.Ty = E->getType();
571   return Ops;
572 }
573 
574 
575 LValue ComplexExprEmitter::
576 EmitCompoundAssignLValue(const CompoundAssignOperator *E,
577           ComplexPairTy (ComplexExprEmitter::*Func)(const BinOpInfo&),
578                          ComplexPairTy &Val) {
579   TestAndClearIgnoreReal();
580   TestAndClearIgnoreImag();
581   QualType LHSTy = E->getLHS()->getType();
582 
583   BinOpInfo OpInfo;
584 
585   // Load the RHS and LHS operands.
586   // __block variables need to have the rhs evaluated first, plus this should
587   // improve codegen a little.
588   OpInfo.Ty = E->getComputationResultType();
589 
590   // The RHS should have been converted to the computation type.
591   assert(OpInfo.Ty->isAnyComplexType());
592   assert(CGF.getContext().hasSameUnqualifiedType(OpInfo.Ty,
593                                                  E->getRHS()->getType()));
594   OpInfo.RHS = Visit(E->getRHS());
595 
596   LValue LHS = CGF.EmitLValue(E->getLHS());
597 
598   // Load from the l-value.
599   ComplexPairTy LHSComplexPair = EmitLoadOfLValue(LHS);
600 
601   OpInfo.LHS = EmitComplexToComplexCast(LHSComplexPair, LHSTy, OpInfo.Ty);
602 
603   // Expand the binary operator.
604   ComplexPairTy Result = (this->*Func)(OpInfo);
605 
606   // Truncate the result back to the LHS type.
607   Result = EmitComplexToComplexCast(Result, OpInfo.Ty, LHSTy);
608   Val = Result;
609 
610   // Store the result value into the LHS lvalue.
611   EmitStoreThroughLValue(Result, LHS);
612 
613   return LHS;
614 }
615 
616 // Compound assignments.
617 ComplexPairTy ComplexExprEmitter::
618 EmitCompoundAssign(const CompoundAssignOperator *E,
619                    ComplexPairTy (ComplexExprEmitter::*Func)(const BinOpInfo&)){
620   ComplexPairTy Val;
621   LValue LV = EmitCompoundAssignLValue(E, Func, Val);
622 
623   // The result of an assignment in C is the assigned r-value.
624   if (!CGF.getContext().getLangOptions().CPlusPlus)
625     return Val;
626 
627   // If the lvalue is non-volatile, return the computed value of the assignment.
628   if (!LV.isVolatileQualified())
629     return Val;
630 
631   return EmitLoadOfComplex(LV.getAddress(), LV.isVolatileQualified());
632 }
633 
634 LValue ComplexExprEmitter::EmitBinAssignLValue(const BinaryOperator *E,
635                                                ComplexPairTy &Val) {
636   assert(CGF.getContext().hasSameUnqualifiedType(E->getLHS()->getType(),
637                                                  E->getRHS()->getType()) &&
638          "Invalid assignment");
639   TestAndClearIgnoreReal();
640   TestAndClearIgnoreImag();
641 
642   // Emit the RHS.  __block variables need the RHS evaluated first.
643   Val = Visit(E->getRHS());
644 
645   // Compute the address to store into.
646   LValue LHS = CGF.EmitLValue(E->getLHS());
647 
648   // Store the result value into the LHS lvalue.
649   EmitStoreThroughLValue(Val, LHS);
650 
651   return LHS;
652 }
653 
654 ComplexPairTy ComplexExprEmitter::VisitBinAssign(const BinaryOperator *E) {
655   ComplexPairTy Val;
656   LValue LV = EmitBinAssignLValue(E, Val);
657 
658   // The result of an assignment in C is the assigned r-value.
659   if (!CGF.getContext().getLangOptions().CPlusPlus)
660     return Val;
661 
662   // If the lvalue is non-volatile, return the computed value of the assignment.
663   if (!LV.isVolatileQualified())
664     return Val;
665 
666   return EmitLoadOfComplex(LV.getAddress(), LV.isVolatileQualified());
667 }
668 
669 ComplexPairTy ComplexExprEmitter::VisitBinComma(const BinaryOperator *E) {
670   CGF.EmitIgnoredExpr(E->getLHS());
671   return Visit(E->getRHS());
672 }
673 
674 ComplexPairTy ComplexExprEmitter::
675 VisitAbstractConditionalOperator(const AbstractConditionalOperator *E) {
676   TestAndClearIgnoreReal();
677   TestAndClearIgnoreImag();
678   llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true");
679   llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false");
680   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end");
681 
682   // Bind the common expression if necessary.
683   CodeGenFunction::OpaqueValueMapping binding(CGF, E);
684 
685   CodeGenFunction::ConditionalEvaluation eval(CGF);
686   CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock);
687 
688   eval.begin(CGF);
689   CGF.EmitBlock(LHSBlock);
690   ComplexPairTy LHS = Visit(E->getTrueExpr());
691   LHSBlock = Builder.GetInsertBlock();
692   CGF.EmitBranch(ContBlock);
693   eval.end(CGF);
694 
695   eval.begin(CGF);
696   CGF.EmitBlock(RHSBlock);
697   ComplexPairTy RHS = Visit(E->getFalseExpr());
698   RHSBlock = Builder.GetInsertBlock();
699   CGF.EmitBlock(ContBlock);
700   eval.end(CGF);
701 
702   // Create a PHI node for the real part.
703   llvm::PHINode *RealPN = Builder.CreatePHI(LHS.first->getType(), 2, "cond.r");
704   RealPN->addIncoming(LHS.first, LHSBlock);
705   RealPN->addIncoming(RHS.first, RHSBlock);
706 
707   // Create a PHI node for the imaginary part.
708   llvm::PHINode *ImagPN = Builder.CreatePHI(LHS.first->getType(), 2, "cond.i");
709   ImagPN->addIncoming(LHS.second, LHSBlock);
710   ImagPN->addIncoming(RHS.second, RHSBlock);
711 
712   return ComplexPairTy(RealPN, ImagPN);
713 }
714 
715 ComplexPairTy ComplexExprEmitter::VisitChooseExpr(ChooseExpr *E) {
716   return Visit(E->getChosenSubExpr(CGF.getContext()));
717 }
718 
719 ComplexPairTy ComplexExprEmitter::VisitInitListExpr(InitListExpr *E) {
720     bool Ignore = TestAndClearIgnoreReal();
721     (void)Ignore;
722     assert (Ignore == false && "init list ignored");
723     Ignore = TestAndClearIgnoreImag();
724     (void)Ignore;
725     assert (Ignore == false && "init list ignored");
726 
727   if (E->getNumInits() == 2) {
728     llvm::Value *Real = CGF.EmitScalarExpr(E->getInit(0));
729     llvm::Value *Imag = CGF.EmitScalarExpr(E->getInit(1));
730     return ComplexPairTy(Real, Imag);
731   } else if (E->getNumInits() == 1) {
732     return Visit(E->getInit(0));
733   }
734 
735   // Empty init list intializes to null
736   assert(E->getNumInits() == 0 && "Unexpected number of inits");
737   QualType Ty = E->getType()->getAs<ComplexType>()->getElementType();
738   llvm::Type* LTy = CGF.ConvertType(Ty);
739   llvm::Value* zeroConstant = llvm::Constant::getNullValue(LTy);
740   return ComplexPairTy(zeroConstant, zeroConstant);
741 }
742 
743 ComplexPairTy ComplexExprEmitter::VisitVAArgExpr(VAArgExpr *E) {
744   llvm::Value *ArgValue = CGF.EmitVAListRef(E->getSubExpr());
745   llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, E->getType());
746 
747   if (!ArgPtr) {
748     CGF.ErrorUnsupported(E, "complex va_arg expression");
749     llvm::Type *EltTy =
750       CGF.ConvertType(E->getType()->getAs<ComplexType>()->getElementType());
751     llvm::Value *U = llvm::UndefValue::get(EltTy);
752     return ComplexPairTy(U, U);
753   }
754 
755   // FIXME Volatility.
756   return EmitLoadOfComplex(ArgPtr, false);
757 }
758 
759 //===----------------------------------------------------------------------===//
760 //                         Entry Point into this File
761 //===----------------------------------------------------------------------===//
762 
763 /// EmitComplexExpr - Emit the computation of the specified expression of
764 /// complex type, ignoring the result.
765 ComplexPairTy CodeGenFunction::EmitComplexExpr(const Expr *E, bool IgnoreReal,
766                                                bool IgnoreImag) {
767   assert(E && E->getType()->isAnyComplexType() &&
768          "Invalid complex expression to emit");
769 
770   return ComplexExprEmitter(*this, IgnoreReal, IgnoreImag)
771     .Visit(const_cast<Expr*>(E));
772 }
773 
774 /// EmitComplexExprIntoAddr - Emit the computation of the specified expression
775 /// of complex type, storing into the specified Value*.
776 void CodeGenFunction::EmitComplexExprIntoAddr(const Expr *E,
777                                               llvm::Value *DestAddr,
778                                               bool DestIsVolatile) {
779   assert(E && E->getType()->isAnyComplexType() &&
780          "Invalid complex expression to emit");
781   ComplexExprEmitter Emitter(*this);
782   ComplexPairTy Val = Emitter.Visit(const_cast<Expr*>(E));
783   Emitter.EmitStoreOfComplex(Val, DestAddr, DestIsVolatile);
784 }
785 
786 /// StoreComplexToAddr - Store a complex number into the specified address.
787 void CodeGenFunction::StoreComplexToAddr(ComplexPairTy V,
788                                          llvm::Value *DestAddr,
789                                          bool DestIsVolatile) {
790   ComplexExprEmitter(*this).EmitStoreOfComplex(V, DestAddr, DestIsVolatile);
791 }
792 
793 /// LoadComplexFromAddr - Load a complex number from the specified address.
794 ComplexPairTy CodeGenFunction::LoadComplexFromAddr(llvm::Value *SrcAddr,
795                                                    bool SrcIsVolatile) {
796   return ComplexExprEmitter(*this).EmitLoadOfComplex(SrcAddr, SrcIsVolatile);
797 }
798 
799 LValue CodeGenFunction::EmitComplexAssignmentLValue(const BinaryOperator *E) {
800   assert(E->getOpcode() == BO_Assign);
801   ComplexPairTy Val; // ignored
802   return ComplexExprEmitter(*this).EmitBinAssignLValue(E, Val);
803 }
804 
805 LValue CodeGenFunction::
806 EmitComplexCompoundAssignmentLValue(const CompoundAssignOperator *E) {
807   ComplexPairTy(ComplexExprEmitter::*Op)(const ComplexExprEmitter::BinOpInfo &);
808   switch (E->getOpcode()) {
809   case BO_MulAssign: Op = &ComplexExprEmitter::EmitBinMul; break;
810   case BO_DivAssign: Op = &ComplexExprEmitter::EmitBinDiv; break;
811   case BO_SubAssign: Op = &ComplexExprEmitter::EmitBinSub; break;
812   case BO_AddAssign: Op = &ComplexExprEmitter::EmitBinAdd; break;
813 
814   default:
815     llvm_unreachable("unexpected complex compound assignment");
816     Op = 0;
817   }
818 
819   ComplexPairTy Val; // ignored
820   return ComplexExprEmitter(*this).EmitCompoundAssignLValue(E, Op, Val);
821 }
822